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- (No Model.) 2 Sheets -shee t 1.

W. s. ANDREWS.- GIRGUIT CONTROLLER FORBLEGTRIG MOTORS.

No. 474,623. Patented May 10, 1892'.

with/WM I wwewboz gg his fltkozmews I EH5 20., mcno-umm, vusmnnru n c v ma non are UNITED STATES PATENT OFFICE.

\VILLIAM S. ANDREWS, OF NEW YORK, N. Y., ASSIGNOR TO THE EDISON GENERAL ELECTRIC COMPANY, OF SAME PLACE.

ClRCUlT-CONTROLLER FOR ELECT-RIC MOTORS.

SPECIFICATION forming part of Letters Patent No. 474,623, dated May 10, 1892.

Application filed May 27, 1891. Serial No. 394,266. (No model.)

To aZZ whom, it may concern.-

Be it known that 1, WILLIAM S. ANDREWS, a citizen of the United States, residing at New York, in the county and State of New York, have invented a certain new and useful Improvement in Circuit-Controllers for Electric Motors, of which the following is a specification.

The present invention relates to means for making and breaking the circuit of electrical instruments or devices, and especially electrical motors. Y

The main object of the. invention is to provide a controller for the motor or other apparatus which shall make and break the circuit in such manneras to fully protect the apparatus from injury and which shall be strong and simpleg-and the invention consists in the apparatus and in the several combinations hereinafter described.

The invention is illustrated in the accompanying drawings, in which- Figure 1 is a plan view of the switch in the open position, showing, also, in diagram the circuit connections. Fig. 2 is also a plan View of the switch, the switch being closed and the handle moved back nearly to its open position. Fig. 3 is a side view of the switch, the handle being broken away on the line a of Fig. 2. Fig.4 is a side view of the handle detached.

The contacts and switching devices are mounted on an insulating-base 1. The contacts consist of one long contact 2, in position to co-operate with the spring 3, carried by the pivoted switch-arm 4, and several smaller contacts 5, in position to co-operatewith the spring 8' at the opposite end of the switcharm. These latter contacts are connected through resistances 6, as usual in rheostats. The opposite end of spring 3' rests on the block 3", through which the pivot-pin passes. The contacts 2 and 5 are so arranged that the switch-arm strikes the contact 2 before it strikes the first contact 5. At one end of the series of contacts 5 is a spring-clip 7, so arranged that when the switch-arm approaches the limit of its movement the lower end is forced under the spring-clip and is held thereby from returning under the influence of the spring 8, which is connected to the switch-arm arm in the direction to break the circuit, and

as soon as the arm is so far withdrawn from the spring-clip 7 that the tension thereof is overcome by the spring 8 the switch-arm is instantly thrown back to its open position and the circuit is broken. While the switchhandle is moving from its position parallel with the switch-arm back to the position in which it is shown in Fig. 2 it moves entirely independent of the switch-arm and of the spring 8.

In Fig. 1, 14 indicates the field-magnet of a motor, and 15 the armature of the same motor. 16 17 are the positive and negative wires of the supply-circuit. The former is connected to the field-magnet, thence by wire 19 to the long contact 2. The pivot of the switch is connected by wire 20 to the binding-post 21, which is connected to the negative wire. The post 18 is connected by wire 22 to the armature and by wire 23 to the last contact 5.

With the circuit connections as above described the operation of the switchwonld be as follows: When the handle is moved toward the left, the switch-arm 3 will first touch the long contact 2, closing the field-magnet circuit and energizing the field-magnet, while the armature-circuit is open. The armature-circuit will next be closed by the contact between the switch-arm and the first contact 5, but all of the resistances 6 will be in series in the armature-circuit. As the handle is moved still farther the resistance-coils are successively cut out of circuit, and finally when a complete movement of the handle has been made all of the resistance is out of the armature-circuit. When the handle is reversed, it moves freely from its position in line with the switch-arm to the position shown in Fig. 2 without affecting the switch-arm or the spring 8. The action already described then takes place, breaking the circuit instantaneously. v

The main advantages of the switch described are that it is impossible to leave the switch-arm on any intermediate resistancec nta a dent lye th r nmaki se r ak- 111g the circuit, since the arm will be thrown to open position by the spring 8 as soon as it is released by the operator. The handle moves freely through the larger part of its movement and then positively engages with the switch-arm to open the switch. The switch also gives a long break when in its open position. In large switches I prefer to employ a dash-pot or similar retarding device, so as to prevent cutting out the resistance too I quickly in closing the motor-circuit.

What I claim is- 1, The combination of apivoted switch-arm, a spring connected thereto and tending to move the arm to its open positioma separately-moyable handle having a lug engaging tact-s being so arranged that one end of the switch-arm makes contact therewith before the other, substantially as described.

2. The combinatiom'in a switch, of a single switch-arm, an operating-spring therefor, conand a handle movable through a part of its 7 range independently of the switch arm and of the spring, substantially as described.

3. The combination, in a switch, of aswitcharm having two switch plates or faces connected to one side of acircuit, along contact in. the path of movement of said switch-arm and connected to the opposite side of thecircuit'through one branch, and a series of contacts connected by resistances also in position to co-operate with the switch-arm after contact has been made with the long contact, said resistances being connected to the circuit through a second branch,substantially as described.

. 4. The combination of a switch-arm, acontact spring or plate at one end thereof, a contact co-operating with said spring or plate, and a contact spring or plate at the opposite end of the switch-arm, the latter spring bearing on a contact at each end, substantially as .described. V

. This specification signed and witnessed this 11th day of May, 1891.

W. S. ANDREWS. Witnesses:

HENRY PRICE BALL, ALDRED K. WARREN. 

